Conduction is a heat transfer mechanism used in electronics design. Even if a system is designed for convection cooling of the circuit boards, conduction is still the dominant heat transfer mechanism for component devices located on circuit boards. This is especially true of power electronics, where concentrations of heat are developed in components. This heat must be transferred via conduction to the component case, the circuit board, or a heat sink before it can be handled by system level cooling mechanisms. Consequently, electronics designers are constantly evaluating new techniques of thermal conduction to dissipate heat from electronic components.
The most critical path for cooling electronics is the interface between the electronic component and the heat sink. Driving constraints are interface thermal resistance, bulk thermal conductivity, machining tolerance range, contamination at the interface joints, electrical isolation, handling cost, and material cost. The prior art addresses these problems using grease, cure in-place thermal bonds, preformed thermal pads, copper tape, copper covered foam pads, metallic or component heat sinks, individual component heat sinks, and single piece skylined heat sinks for all or part of a printed wiring board (PWB). The term “skylined” refers to the cross sectional profile formed by a plurality of electronic components on a PWB, as the varying heights or thicknesses of the electronic components give the appearance of a city skyline.